1 files changed, 68 insertions, 0 deletions
diff --git a/layout/mathml/nsMathMLmrowFrame.cpp b/layout/mathml/nsMathMLmrowFrame.cpp
new file mode 100644
index 0000000000..abff988585
--- /dev/null
+++ b/layout/mathml/nsMathMLmrowFrame.cpp
@@ -0,0 +1,68 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsMathMLmrowFrame.h"
+
+#include "mozilla/PresShell.h"
+#include "mozilla/gfx/2D.h"
+
+using namespace mozilla;
+
+//
+// <mrow> -- horizontally group any number of subexpressions - implementation
+//
+
+nsIFrame* NS_NewMathMLmrowFrame(PresShell* aPresShell, ComputedStyle* aStyle) {
+  return new (aPresShell)
+      nsMathMLmrowFrame(aStyle, aPresShell->GetPresContext());
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmrowFrame)
+
+nsMathMLmrowFrame::~nsMathMLmrowFrame() = default;
+
+NS_IMETHODIMP
+nsMathMLmrowFrame::InheritAutomaticData(nsIFrame* aParent) {
+  // let the base class get the default from our parent
+  nsMathMLContainerFrame::InheritAutomaticData(aParent);
+
+  mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY;
+
+  return NS_OK;
+}
+
+nsresult nsMathMLmrowFrame::AttributeChanged(int32_t aNameSpaceID,
+                                             nsAtom* aAttribute,
+                                             int32_t aModType) {
+  // Special for <mtable>: In the frame construction code, we also use
+  // this frame class as a wrapper for mtable. Hence, we should pass the
+  // notification to the real mtable
+  if (mContent->IsMathMLElement(nsGkAtoms::mtable_)) {
+    nsIFrame* frame = mFrames.FirstChild();
+    for (; frame; frame = frame->PrincipalChildList().FirstChild()) {
+      // drill down to the real mtable
+      if (frame->IsTableWrapperFrame())
+        return frame->AttributeChanged(aNameSpaceID, aAttribute, aModType);
+    }
+    MOZ_ASSERT_UNREACHABLE("mtable wrapper without the real table frame");
+  }
+
+  return nsMathMLContainerFrame::AttributeChanged(aNameSpaceID, aAttribute,
+                                                  aModType);
+}
+
+/* virtual */
+eMathMLFrameType nsMathMLmrowFrame::GetMathMLFrameType() {
+  if (!IsMrowLike()) {
+    nsIMathMLFrame* child = do_QueryFrame(mFrames.FirstChild());
+    if (child) {
+      // We only have one child, so we return the frame type of that child as if
+      // we didn't exist.
+      return child->GetMathMLFrameType();
+    }
+  }
+  return nsMathMLFrame::GetMathMLFrameType();
+}